Mine is inspired from a movie/movie character. Those who have seen the movie "Donnie Darko" will know where my nickname comes from right away. I just really like the main character in the movie because I see myself in him.
You should really see the movie if you haven't seen it yet, an amazing masterpiece (#126 in IMBD's All Time Top 250 movies with an 8.3):
http://www.imdb.com/title/tt0246578/
Some quotes from the movie to further explain:
Donnie: Do you want your sister to lose weight? Tell her to get off the couch, stop eating twinkies and maybe go out for field hockey. You know what? No one ever knows what they want to be when they grow up. You know it takes a little, little while to find that out, right, Jim? And you... yeah, you. Sick of some jerk shoving your head down the toilet? Well, you know what? Maybe... you should lift some weights, or uh, take a karate lesson and the next time he's tries to do it, you kick him in the balls.
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Gretchen: Donnie Darko? What the hell kind of name is that? It's like some sort of superhero or something
Donnie: What makes you think I'm not?
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Dr. Lilian Thurman: Do you still think about girls a lot?
Donnie: [Under hypnosis] Yeah.
Dr. Lilian Thurman: How are things going at school?
Donnie: I think about girls a lot.
Dr. Lilian Thurman: I asked you about school, Donnie.
Donnie: I think about fucking a lot, in school.
Dr. Lilian Thurman: What else do you think about, when you're at school?
Donnie: Married With Children.
Dr. Lilian Thurman: Do you think about your family?
Donnie: I just turn down the volume and think about fucking Christina Applegate.
Dr. Lilian Thurman: I asked you about your family.
Donnie: [Chuckling] No, I don't think about fucking my family, that's gross.